Restraint configured to allow relative heel/forefoot motion

Abstract

Shoes and/or shoe elements facilitate natural foot motion and/or reduce forces tending to fight natural foot motion. In at least some such structures, a wearer's heel is secured to the hindfoot region of a shoe (e.g., by a strap system) in a manner that permits heel/forefoot rotation and that allows the lower leg to remain straight. In other structures, a shoe can include a heel supporting component that is separate from a midsole component, and this heel supporting component can move toward the lateral side and/or medial side of the shoe along an interface between the heel supporting component and the midsole component. Other suitable shoe and shoe component structures also are described.

The invention claimed is: 
     
       1. An article of footwear comprising:
 a sole structure including forefoot and hindfoot regions, wherein the forefoot and hindfoot regions are respectively configured for location under a forefoot and a hindfoot when the article is worn by a human wearer; 
 an upper that includes an inner element, an outer element, and a forefoot part, wherein
 the forefoot part is coupled to the sole structure in the forefoot region and is configured to substantially cover sides and a top of the forefoot when the article is worn by the human wearer, 
 the outer element being a single continuous piece of material that covers substantially all of the forefoot, substantially all of a midfoot and portions of the hindfoot when the article is worn by the human wearer, the outer element including a plurality of reinforcing strands embedded in the outer element, an opening in an instep region of the upper, and eyelets on each of medial and lateral sides of the opening, wherein the outer element includes a medial opening and a lateral opening, and the reinforcing strands are exposed in the medial and lateral openings, 
 the inner element covers substantially the entire wearer's foot when the article is worn by the human wearer, and 
 the inner element is movable within the outer element; and 
 
 a strap system, wherein the strap system includes an ankle strap, a lateral heel strap and a medial heel strap, wherein the strap system is part of the inner element, wherein a medial end of the ankle strap is located forward of the medial heel strap and includes a lace eyelet formed therein, wherein a lateral end of the ankle strap is located forward of the lateral heel strap and includes a lace eyelet formed therein, wherein the strap system is asymmetric in that the lateral heel strap is shorter and more rearward than the medial heel strap, wherein the lateral and medial ends of the ankle strap are configured to be connected to and unconnected from one another, and 
 wherein the strap system is configured such that, when the article is worn by the human wearer,
 the ankle strap completely surrounds and is secured to the wearer's ankle, 
 the lateral heel strap extends from under a wearer lateral malleolus to a lateral anchor location under a heel of the wearer's foot, and 
 the medial heel strap extends from under a wearer medial malleolus to a medial anchor location under the heel of the wearer's foot. 
 
 
     
     
       2. The article of footwear of  claim 1 , wherein the lateral heel strap comprises flexible foam extending continuously from the ankle strap to a lower edge of the inner element on a lateral side of the upper and the medial heel strap comprises flexible foam extending continuously from the ankle strap to the lower edge of the inner element on a medial side of the upper. 
     
     
       3. The article of footwear of  claim 1 , wherein the strap system comprises a continuous piece of flexible foam extending from a lower edge of the inner element on a lateral side of the upper, through the ankle strap, and to the lower edge of the inner element on a medial side of the upper. 
     
     
       4. The article of footwear of  claim 3 , wherein the strap system comprises a panel of tensile material bonded to the continuous piece of flexible foam. 
     
     
       5. The article of footwear of  claim 1 , wherein the inner element comprises
 a heel element formed of flexible foam and filling a space bounded by a rear edge of the lateral heel strap, a rear edge of the medial heel strap, and a lower edge of a rear portion of the ankle strap extending from the lateral heel strap to the medial heel strap, 
 a lateral element formed of flexible foam and extending from a forward edge of the lateral heel strap to a toe region, a rear edge of the lateral element abutting the forward edge of the lateral heel strap, and 
 a medial element formed of flexible foam and extending from a forward edge of the medial heel strap to the toe region, a rear edge of the medial element abutting the forward edge of the medial heel strap. 
 
     
     
       6. The article of footwear of  claim 5 , wherein the strap system comprises a continuous piece of flexible foam extending from a lower edge of the inner element on a lateral side of the upper, through the ankle strap, and to the lower edge of the inner element on a medial side of the upper. 
     
     
       7. The article of footwear of  claim 6 , wherein the strap system comprises a panel of tensile material bonded to the continuous piece of flexible foam. 
     
     
       8. The article of footwear of  claim 7 , wherein
 the lower edge of the inner element follows a perimeter of the sole structure, 
 a lower edge of the outer element follows the perimeter of the sole structure, 
 the lower edge of the inner element and the lower edge of the outer element are coupled to each other and to the sole structure at locations forward of a forward edge of the lateral heel strap, locations forward of a forward edge of the medial heel strap, locations rearward of a rear edge of the lateral heel strap and locations rearward of a rear edge of the medial heel strap. 
 
     
     
       9. An article of footwear, comprising:
 a sole structure; and 
 an upper having forefoot, midfoot, and hindfoot regions and including an inner element and an outer element, wherein
 the outer element being a single continuous piece of material that covers substantially all of the forefoot region, substantially all of the midfoot region and portions of the hindfoot region, the outer element including a plurality of reinforcing strands embedded in the outer element, an opening in an instep region of the upper, and eyelets on each of medial and lateral sides of the opening, wherein the outer element includes a medial opening and a lateral opening, and the reinforcing strands are exposed in the medial and lateral openings, 
 the inner element covers substantially all of the forefoot, midfoot and hindfoot regions, 
 the inner element is movable within the outer element and includes a strap system, a heel element, a lateral element, and a medial element, 
 the strap system includes an ankle strap, a lateral heel strap and a medial heel strap, 
 the heel element is formed of flexible foam and fills a space bounded by a rear edge of the lateral heel strap, a rear edge of the medial heel strap, and a lower edge of a rear portion of the ankle strap extending from the lateral heel strap to the medial heel strap, 
 the lateral element is formed of flexible foam and extends from a forward edge of the lateral heel strap to a toe region, a rear edge of the lateral element abutting the forward edge of the lateral heel strap, 
 the medial element is formed of flexible foam and extends from a forward edge of the medial heel strap to the toe region, a rear edge of the medial element abutting the forward edge of the medial heel strap, 
 the strap system comprises a continuous piece of flexible foam extending from a lower edge of the inner element on a lateral side of the upper, through the ankle strap, and to the lower edge of the inner element on a medial side of the upper, and 
 the strap system is substantially inelastic and the heel element, the lateral element and the medial element are elastic, 
 
 wherein a medial end of the ankle strap is located forward of the medial heel strap and a lateral end of the ankle strap is located forward of the lateral heel strap wherein the strap system is asymmetric in that the lateral heel strap is shorter and more rearward than the medial heel strap, wherein the lateral and medial ends of the ankle strap are configured to be connected to and unconnected from one another. 
 
     
     
       10. The article of footwear of  claim 9 , wherein
 the lower edge of the inner element follows a perimeter of the sole structure, 
 a lower edge of the outer element follows the perimeter of the sole structure, 
 the lower edge of the inner element and the lower edge of the outer element are coupled to each other and to the sole structure at locations forward of a forward edge of the lateral heel strap, locations forward of a forward edge of the medial heel strap forward edge, locations rearward of a rear edge of the lateral heel strap and locations rearward of a rear edge of the medial heel strap. 
 
     
     
       11. The article of footwear of  claim 9 , wherein a medial end of the ankle strap is located forward of the medial heel strap and includes a lace eyelet formed therein, and wherein a lateral end of the ankle strap is located forward of the lateral heel strap and includes a lace eyelet formed therein. 
     
     
       12. The article of footwear of  claim 11 , wherein the outer element includes a first plurality of eyelets on a lateral side of an instep region and a second plurality of eyelets on a medial side of the instep region, and further comprising a lace threaded through the first plurality of eyelets, the second plurality of eyelets, the lace eyelet formed in the medial end of the ankle strap, and the lace eyelet formed in the lateral end of the ankle strap. 
     
     
       13. The article of footwear of  claim 9 , wherein the strap system comprises a panel of tensile material bonded to the continuous piece of flexible foam. 
     
     
       14. The article of footwear of  claim 13 , wherein
 the lower edge of the inner element follows a perimeter of the sole structure, 
 a lower edge of the outer element follows the perimeter of the sole structure, 
 the lower edge of the inner element and the lower edge of the outer element are coupled to each other and to the sole structure at locations forward of a forward edge of the lateral heel strap, locations forward of a forward edge of the medial heel strap, locations rearward of a rear edge of the lateral heel strap and locations rearward of a rear edge of the medial heel strap. 
 
     
     
       15. The article of footwear of  claim 14 , wherein a lower edge of the heel element coincides with a portion of the lower edge of the inner element in the hindfoot region, a lower edge of the medial element coincides with a portion of the lower edge of the inner element on the medial side in the midfoot and the forefoot regions, a top edge of the medial element is located in an instep region on the medial side, a lower edge of the lateral element coincides with a portion of the lower edge of the inner element on the lateral side in the midfoot and the forefoot regions, and a top edge of the lateral element is located in the instep region on the lateral side.